Contempt of court for nonpayment of support has many possible outcomes: everything from working out a payment plan to garnishment of wages to seizure of assets to license suspension to jail.
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If the court finds that he has the ability to pay and is willfully choosing not to do so, then they can find him to be in contempt. Penalties vary from being put in jail with a "purge" amount (an amount he has to pay before he can get out of jail) to suspension of his drivers' license or the structuring of a payment plan towards the past due child support payments.
Please note that THESE COMMENTS ARE NOT INTENDED AS LEGAL ADVICE and are for informational purposes only. This response is not intended to create any attorney-client relationship and is only based on the limited facts given. The response might change should additional facts be learned and should not be relied on as legal advice. It is recommended that you consult with an attorney who can properly assess the situation, as well as all pertinent facts, prior to taking any action based on the foregoing statements.
You will be given a chance to testify (tell the DOR attorney that you want to) so bring as much proof as you have as to his job hopping, quitting jobs, assets he may have, etc. Your testimony can often make the difference between a large purge or a slap on the wrist. If it helps, have a prepared statement to read to the Judge - just keep it brief.
Family law rules differ significantly in every state, especially procedural rules. Always seek the advice of an attorney in the state where your divorce was filed.